<template>
  <div>
    <span>全选:</span>
    <input v-model=full type="checkbox" />
    <button @click="add">反选</button>
    <ul>
      <li v-for="(item,index) in arr" :key=index>
        <input v-model=item.c type="checkbox" />
        <span>{{item.name}}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [
        {
          name: "猪八戒",
          c: false,
        },
        {
          name: "孙悟空",
          c: false,
        },
        {
          name: "唐僧",
          c: false,
        },
        {
          name: "白龙马",
          c: false,
        },
      ],
    };
  },
  computed:{
    full:{
      get(){
        return this.arr.every(item=>item.c)
      }
    },
    set(val){
      console.log(val);
      this.arr.forEach(item=>item.c=val)
    }
  },
  methods:{
     add(){
      this.list.forEach(item=>item.c=!item.c)
     }
  }
};
</script>

<style>
</style>